Police are investigating an attempted armed robbery that occurred at a South Townsville convenience store this morning.

Shortly after 5am a man entered the shop on Boundary Street and produced a metal bar.

He threatened a male employee and demanded money from the till.

The employee was struck in the face after attempting to tackle the offender, who then made further demands for cash from the Automatic Teller Machine.

The employee fled the store and started calling for assistance. The offender fled the store empty handed.

The male employee sustained facial bruising and a laceration on his lip.

The man was last seen running from the store. He is described as being Caucasian, around 180cm tall with a proportionate build. He was wearing a black long sleeve shirt and black jeans.

Police would like to speak to anyone who may have witnessed the incident